package com.study.common.util.file;

import java.io.File;
import java.io.IOException;

import org.apache.commons.io.FilenameUtils;
import org.springframework.web.multipart.MultipartFile;

import com.study.common.config.Global;
import com.study.common.exception.file.FileNameLengthLimitExceededException;
import com.study.common.exception.file.FileSizeLimitExceededException;
import com.study.common.exception.file.InvalidExtensionException;
import com.study.common.util.DateUtils;
import com.study.common.util.Md5Utils;
import com.study.common.util.StringUtils;

/**
 * 文件上传工具
 */
public class FileUploadUtils {
	/**
	 * 默认大小 50M
	 */
	public static final long DEFAULT_MAX_SIZE = 50 * 1024 * 1024;

	/**
	 * 默认的文件名最大长度 100
	 */
	public static final int DEFAULT_FILE_NAME_LENGTH = 100;

	/**
	 * 默认上传的地址
	 */
	private static String defaultBaseDir = Global.getProfile();

	private static int counter = 0;

	public static void setDefaultBaseDir(String defaultBaseDir) {
		FileUploadUtils.defaultBaseDir = defaultBaseDir;
	}

	public static String getDefaultBaseDir() {
		return defaultBaseDir;
	}

	/**
	 * 以默认配置进行文件上传
	 *
	 * @param file 上传的文件
	 * @return 文件名称
	 * @throws Exception
	 */
	public static final String upload(MultipartFile file) throws IOException {
		try {
			return upload(getDefaultBaseDir(), file, MimeTypeUtils.DEFAULT_ALLOWED_EXTENSION);
		} catch (Exception e) {
			throw new IOException(e.getMessage(), e);
		}
	}

	/**
	 * 根据文件路径上传
	 *
	 * @param baseDir 相对应用的基目录
	 * @param file    上传的文件
	 * @return 文件名称
	 * @throws IOException
	 */
	public static final String upload(String baseDir, MultipartFile file) throws IOException {
		try {
			return upload(baseDir, file, MimeTypeUtils.DEFAULT_ALLOWED_EXTENSION);
		} catch (Exception e) {
			throw new IOException(e.getMessage(), e);
		}
	}
	
	/**
	 * 上传到指定的文件夹
	 * @param baseDir  根目录
	 * @param midDir   指定文件夹
	 * @param file     文件
	 * @return
	 * @throws IOException
	 */
	public static String upload(String baseDir,String midDir,MultipartFile file) throws IOException {
	    try {
            return uploadZhiding(baseDir, midDir,file, MimeTypeUtils.DEFAULT_ALLOWED_EXTENSION);
        } catch (Exception e) {
            throw new IOException(e.getMessage(), e);
        }
	}
	
	
	/**
     * 文件上传到指定的文件夹
     *
     * @param baseDir   相对应用的基目录
     * @param midDir    指定的文件夹,后面需要添加斜杠/
     * @param file      上传的文件
     * @param extension 上传文件类型
     * @return 返回上传成功的文件名
     * @throws FileSizeLimitExceededException       如果超出最大大小
     * @throws FileNameLengthLimitExceededException 文件名太长
     * @throws IOException                          比如读写文件出错时
     * @throws InvalidExtensionException            文件校验异常
     */
    public static final String uploadZhiding(String baseDir,String midDir, MultipartFile file, String[] allowedExtension)
            throws FileSizeLimitExceededException, IOException, FileNameLengthLimitExceededException,
            InvalidExtensionException {
        int fileNamelength = file.getOriginalFilename().length();
        if (fileNamelength > FileUploadUtils.DEFAULT_FILE_NAME_LENGTH) {
            throw new FileNameLengthLimitExceededException(FileUploadUtils.DEFAULT_FILE_NAME_LENGTH);
        }

        assertAllowed(file, allowedExtension);

        String originalName = file.getOriginalFilename();
        String fileName = midDir + System.currentTimeMillis() + originalName;
        File desc = getAbsoluteFile(baseDir, fileName);
        file.transferTo(desc);
        String pathFileName = getPathFileName(baseDir, fileName);
        return pathFileName;
    }
	

	/**
	 * 文件上传
	 *
	 * @param baseDir   相对应用的基目录
	 * @param file      上传的文件
	 * @param extension 上传文件类型
	 * @return 返回上传成功的文件名
	 * @throws FileSizeLimitExceededException       如果超出最大大小
	 * @throws FileNameLengthLimitExceededException 文件名太长
	 * @throws IOException                          比如读写文件出错时
	 * @throws InvalidExtensionException            文件校验异常
	 */
	public static final String upload(String baseDir, MultipartFile file, String[] allowedExtension)
			throws FileSizeLimitExceededException, IOException, FileNameLengthLimitExceededException,
			InvalidExtensionException {
		int fileNamelength = file.getOriginalFilename().length();
		if (fileNamelength > FileUploadUtils.DEFAULT_FILE_NAME_LENGTH) {
			throw new FileNameLengthLimitExceededException(FileUploadUtils.DEFAULT_FILE_NAME_LENGTH);
		}

		assertAllowed(file, allowedExtension);

		String fileName = extractFilename(file);

		File desc = getAbsoluteFile(baseDir, fileName);
		file.transferTo(desc);
		String pathFileName = getPathFileName(baseDir, fileName);
		return pathFileName;
	}

	/**
	 * 编码文件名
	 */
	public static final String extractFilename(MultipartFile file) {
		String fileName = file.getOriginalFilename();
		String extension = getExtension(file);
		fileName = DateUtils.datePath() + "/" + encodingFilename(fileName) + "." + extension;
		return fileName;
	}

	private static final File getAbsoluteFile(String uploadDir, String fileName) throws IOException {
		File desc = new File(uploadDir + File.separator + fileName);

		if (!desc.getParentFile().exists()) {
			desc.getParentFile().mkdirs();
		}
		if (!desc.exists()) {
			desc.createNewFile();
		}
		return desc;
	}

	private static final String getPathFileName(String uploadDir, String fileName) throws IOException {
		int dirLastIndex = uploadDir.lastIndexOf("/") + 1;
		String currentDir = StringUtils.substring(uploadDir, dirLastIndex);
		String pathFileName = "/profile/" + currentDir + "/" + fileName;
		return pathFileName;
	}

	/**
	 * 编码文件名
	 */
	private static final String encodingFilename(String fileName) {
		fileName = fileName.replace("_", " ");
		fileName = Md5Utils.hash(fileName + System.nanoTime() + counter++);
		return fileName;
	}

	/**
	 * 文件大小校验
	 *
	 * @param file 上传的文件
	 * @return
	 * @throws FileSizeLimitExceededException 如果超出最大大小
	 * @throws InvalidExtensionException
	 */
	public static final void assertAllowed(MultipartFile file, String[] allowedExtension)
			throws FileSizeLimitExceededException, InvalidExtensionException {
		long size = file.getSize();
		if (DEFAULT_MAX_SIZE != -1 && size > DEFAULT_MAX_SIZE) {
			throw new FileSizeLimitExceededException(DEFAULT_MAX_SIZE / 1024 / 1024);
		}

		String fileName = file.getOriginalFilename();
		String extension = getExtension(file);
		if (allowedExtension != null && !isAllowedExtension(extension, allowedExtension)) {
			if (allowedExtension == MimeTypeUtils.IMAGE_EXTENSION) {
				throw new InvalidExtensionException.InvalidImageExtensionException(allowedExtension, extension,
						fileName);
			} else if (allowedExtension == MimeTypeUtils.FLASH_EXTENSION) {
				throw new InvalidExtensionException.InvalidFlashExtensionException(allowedExtension, extension,
						fileName);
			} else if (allowedExtension == MimeTypeUtils.MEDIA_EXTENSION) {
				throw new InvalidExtensionException.InvalidMediaExtensionException(allowedExtension, extension,
						fileName);
			} else {
				throw new InvalidExtensionException(allowedExtension, extension, fileName);
			}
		}

	}

	/**
	 * 判断MIME类型是否是允许的MIME类型
	 *
	 * @param extension
	 * @param allowedExtension
	 * @return
	 */
	public static final boolean isAllowedExtension(String extension, String[] allowedExtension) {
		for (String str : allowedExtension) {
			if (str.equalsIgnoreCase(extension)) {
				return true;
			}
		}
		return false;
	}

	/**
	 * 获取文件名的后缀
	 * 
	 * @param file 表单文件
	 * @return 后缀名
	 */
	public static final String getExtension(MultipartFile file) {
		String extension = FilenameUtils.getExtension(file.getOriginalFilename());
		if (StringUtils.isEmpty(extension)) {
			extension = MimeTypeUtils.getExtension(file.getContentType());
		}
		return extension;
	}
}
